The greatest problem in the manufacture of brushes consists in fixing the bristles. On the one hand, it must be possible to fix a sufficiently high number of bristles, in order to obtain the desired density of the bristle pack formed of the bristles. On the other hand, it must be ensured that the bristles are fixed in a reliable way, so that they do not fall out during usage.
One fixing method consists in inserting the bristles into a sleeve as a dense pack and adhering the ends of the bristles arranged in the sleeve to each other, for example by synthetic resin. Subsequently, the handle of the brush is connected with the sleeve. With this fixing method a very dense bristle pack can be obtained. However, the individual bristles are not held in a particularly reliable way. Another fixing method consists in fixing the bristles in holes by means of small clips, for example in a wooden body. With this fixing method it is possible in principle to fix the bristles comparatively well. However, the holes used for accommodating the bristles must have a comparatively great distance from each other, as otherwise the body containing the holes has no sufficient strength to hold the clips. The necessary distance of the holes from each other leads to the fact that the bristle pack is not particularly dense. This problem becomes even worse when natural bristles are used as bristles, for example pig hair. While, for example in synthetic bristles the clip can be arranged in the center of the U-shaped bristles and both ends of the bristle can be utilized, only one end can be utilized in bristles made of pig hair, namely the end opposite to the hair root. Hence it follows that the bristles must be designed longer than the actual bristle pack, since the end portion located in the interior of the brush is bent, so that it can be fixed by the clip. This is disadvantageous in terms of cost, since natural bristles are particularly expensive. In addition, a very small density of the bristle pack is obtained.
A brush should have low manufacturing costs, a dense bristle pack, and a reliable fixation of the individual bristles.